Age resisting rubber and rubber compounds



Patented Oct. 10, 1933 COMPOUNDS Harold A. Morton, Akron, Ohio No Drawing. Application July 14, 1928' a Serial No. 292,906

43 Claims. (Cl. 1s-50 My invention relates to rubber or rubber-like compounds and its object is primarily to increase the age-resisting qualities thereof.

The invention consists in the introductioninto the compound prior to vulcanization, or the application to a vulcanized article, of an appropriate derivative of hydroglyoxaline.

There are a great number of these derivatives which function as anti-oxidants, some of which possess material accelerating properties when introduced into a rubber compound, and others of which exhibit negligible "accelerating properties, and both are within the-purview tion, broadly considered.

Such derivatives which do not exhibit accelerating properties are of special importance under certain factory conditions, since they may be used Without materiallyaffecting factory proa cedure or changing the .rate of cure of an established or selected compound.

Thereare a great number of such hydroglyoxaline derivatives which function as anti-oxidants. All these derivatives are designated in this: specification by the, accustomed nomenclature 'now in general use. The basic material, glyoxal'ine, from which these substances are derived, is usually given the following chemical constitution:

The substances described in this specification are hydroglyoxalines or substituted hydroglyoxalines.

Substituted di hydroglyoxalines in general may be used and as an example, 2-4-5 triphenyl di hydroglyoxaline may be noted, .the chemical formula of which is:

Other examplesare 2-4-5 trifuryl dihydrogly= oxaline and. 24:5 tritolyl di hydroglyoxaline;

Typicalrubber-ilike compounds, or mixtures,

of my invenhaving one of-the described anti-oxidant agents incorporated therein, are as follows: f

Slabs are cured thepress forperiods of 70 minutes and 9.0 minutes at pounds steam pressure and "test strips were then cut out and tested for aging quall'lties, both by the oxygen bomb method fand;hot oven method.

oxygen bomb tesi"i48.hrs. a: 60C. a: s00# Cure'75 x 40ft Curex 40# Com- Tensile Elongation Tensile Elongation pound Orig. Final Orig. Final Orig. Final Orig. Final Per- Per- Per- Percent cent cent cent A 3815 1595 730 550 3700 1570 720 530 B 3815 2690 700 590 3720 2410 700 590 Hot oven-tempe1'ature 150C? Oure75 x 40ft Cure 90 x 40# Daysin i oven 7 stock A i Stock 13 Stock A Stool; Tens. Elong. Tens. Elong. Tens. Elong. Tens. Elong.

Per- Per- I 7 Per- Percent cent' cent cent" Orig. 3815 H v 730 3815 700 3700 720 3720 700 2 day 3695 G90 3110 610 3625 660 3590 V 620 10 days 2660 i 550 3150 560 2510 500 3210 560 17 days 2130 500 2950 500 2145 440 2900 480 24 days" 1685 410 2030 490' 16 20 370 2520 440 ated aging: show. that .thecompounds containing U riacowcocooawoau eral hours.

C Hz-N 2-4-5 trifuryl dihydroglyoxaline age in a much superior manner to the compound not containing this material.

It is also within the purview of this invention to use derivatives of di hydroglyoxaline wherein the double bond between the 4-5 carbon atoms has been saturated by hydrogen; for example, 1-3 diphenyl tetra hydroglyoxaline may be used, the formula for which is:

This material may be prepared by heating 1-2 Similar materials are:

3 di ortho tolyl tetra hydroglyoxaline,

(11 para tolyl tetra hydroglyoxaline,

di xylyl tetra liydroglyoxaline,

di alpha naphthyl tetra hydroglyoxaline, henyl 3-orth0 tolyl tetra hydroglyoxaline, henyl 3-a1pl1a naphthyl tetra hydroglyoxaline.

d1 phenyl 2-propyl tetra hydroglyoxaline, diphenyl 2-vinyl tetra hydroglyoxaline, dlphenyl 2-metl1yl tetra llydroglyoxaline, diphenyl 2-propeny1 tetra hydroglyoxaline,

diphenyl 2-furyl tetra hydroglyoxaline, diphenyl 2-hexyl tetra hydroglyoxaline;

triphenyl tetra hydroglyoxaline, 'phenyl 2-methoethyl tetra liydroglyoxaline,

para tolyl'2-met11y1 tetra hydroglyoxaline,

xylyl 2-fu1y1 tetra hydroglyoxaline,

'phenyl 2-thio tetra hydroglyoxaline,

para tol l 2-phenyl tetra hydroglyoxaline,

diphenyl 4-methvl tetra hydroglyoxaline,

di xylyl 4-methyl tetra hydroglyoxaline,

diphenyl 4-ethyl tetra hydroglyoxaline .di para tolyl 4-ethyl tetra hydroglyoxahne,

diphenyl 4-pseudo butyl tetra hydroglyoxaline,

diphenyl 3-beta naphthyl tetra hydroglyoxaline, henyl 3-beta naphthyl 2-furyl tetra liydroglyoxaline,

' alpha naphthyl Z-propyl tetra hydroglyoxaline,

ortho tolyl 2-propyl tetra hydroglyoxaline,

nyl 3-para tolyl 2-thio tetra hydroglyoxaline, o tolyl 3 xylyl 2-thio tetra hydroglyoxaline.

' beta nap ithyl 2-methyltetra hydroglyoxaline, nyl 3-0rth0 tolyl 2-propyl tetra hydroglyoxaline,

di ortho tolyl Jr-methyl tetra hydroglyoxaline. di para tolyl Jr-methyl tetra hydroglyoxaline.

di alpha naphthyl 2-methy1 tetra hydroglyoxalina.

aldehyde.

alpha naphthyl 2-propenyl tetra hydroglyoxaline, alpha naphthyl 2-phenyltetra hydroglyoxaline,

di alph naphthyl 4-methyl tetra h droglyoxaline, di beta naphthyl 4-]:nethy1 tetra by roglyoxaline,

l-3 diphenyl Z-propyl tetra hydroglyoxaline, the chemical formula being:

CH2-N\ 1 CH. 011201120113 CH2-N/ 1-3 diphenyl 2-propyl tetra hydroglyoxaline can be prepared by heating 100 parts of 1-2 di (phenyl amino) ethane dissolved in alcohol with 4.0 partsrof butyric aldehyde under reflux for sev- Upon cooling and crystallizing there is obtained a cream-colored solid, which is dried and is then ready for use.

To illustrate the use of 1-3 di alpha naphthyl tetra hydroglyoxaline in a black stock accelerated by diphenyl guanidine, the following rubber batches were compounded and mixed, the quantities being expressed in parts per hundred:

An accelerated hot oven test was made on the above stocks cured in a press for '70 and 90 minutes at 40 pounds steam pressure. The results are as To illustrate the use of l-3 diphenyl 2-propyl tetra hydroglyoxaline in a black compounded stock accelerated by diphenyl guanidine, the following mixtures were prepared:

Compound A B Rubber 56. 8 55. 8 Zinc oxide 16.5 16.5 Sulpl1ur 25 2. 25 Mineral oil 4. 0 3.5 Carbon Blac 20.0 20. 0 Diphenyl guanid 0.45 0.45 l-3 diphenyl 2-propyl tetra hydrogly 0. l. 5

Slabs were cured in a press for and 100 min. utes. at 40 pounds steam pressure and test strips were then cut out and tested for aging qualities both by the oxygen bomb oven method.

method and the hot "Oxygen bomb test-48 hrs. a: 60 C. :1: 300# oxygen Cure 80' x 40# Cure 100 X 40# Comp mm d Tensile Elongation Tensile I Elongation Orig. Final Orig. Final Orig. Final Orig. Final Per- Per- Per- Percent cent cent cent A 3290 1025 620 400 3380 880 600 380 B 3300 1970 630 510 3340 1950 620 500 Hot oven age testtemperature 150 F.

Cure 80' x 40# Cure 100 x 40# Days in oven Stock A Stock B Stock A Stock 13 Tens. Elong. Tens. Elong. Tens. Elong. Tens. Elong.

Per- Per- Per- Percent cent cent cent Orig 3045 610 3100 620 3135 650 3195 670 3 2990 570 3175 020 2820 560 3120 620 6 2700 560 3050 550 2425 510 3040 600 9 2305 530 2900 540 2130 470 2920 570 12 2010 480 2780 540 1910 460 2710 540 15 1815 470 2425 490 1610 440 2470 540 To illustrate the use of 1-3 di para tolyl Z-phenyl tetra hydroglyoxaline, the following rubber mix- 150 tures were prepared; "the -;quantities"ibing expressed 'in parts-per hundred:

A "Compound (B- Rubber :55. 81 56.8 Zinc oxide 11.55 11. Snlnhnr 2.25 2.25 Mineral oil :5. 0 f3. 5 Carbon block 24. 0'. 24,0 Alpha-ethyl beta propyl acryl' aniline 0. 4? 0. 4 1-3 di-para tolyl 2-pheny1 tetra hydroglyoxaline 0. 1.5

Slabs were cured in thepress for periods of "70 and 90 minutes at 40 pounds steam pressure and test strips wereftheniout and testedzfor aging qualities both by the oxygen bomb method and the .hotoven' method. J

Oxygen bomb te st-48 hrs. a: '60 C'."a: 300# 5: 35 V Tensile Elongation Tensile Elongation Orig. Final Orig. r1551 ori Final "o ig; Final centcent .cent cent A 3305 1135 700 440 3560 -995 .680 390 B 3265 2540 7620 550 3620 2465 610 .520

Hot ovenxzge testtemperature 150 F.

The useoi 1-3 diphenyl Z-propenfltetra hydroglyoxaline is. illustrated inthis'. example:

Oxygen' bomb test*- 48 :hrs.- I x C. 3005i.

' 5 -oxygen Cute 1; 40:5 Curd-90! x i40# V 280 Com- .1 pound -Tens1le Elongation Tensile Elongation Orig. Final. Orig. Final. Orig. Final. Orig. vFinal -Per- 'Per Per- 'Per- I -cent centcent cent A 3910 1280 700 r 520 3800 1070 700 1460 B 3900 2845 710 060 3725 2735 -700 630 .Hotoven. test,temnerature 150 C'.

0115570 x 40# Cure 90. X 40# Days:

in Stock A Stock B Stock A Stock B oven p p v V p I 'Tens.' Elong'. Tens. Elong. 'lens'; Elong. Tens.'E1ong.

Per- Perv .Per- Percent cent cent cent 0 3910 700 "3900 710 3800 "700 3825 700 2 3960 700 v 3870 700 3570 640 3835 680 0 10 3160 570 3580 650 2760 520 3530 5 650 0 14. V 2025 A60 3350 "650 -2205 440 3210 540 18 1580 450 2670 560 1515 350 I 2510 470 20- 1205 "310 2245 450 1005 200 2000 390 .-.As' a,-.further examplethe use of 1-3 di para. toi'yl vZemethyl tetra E.hydrog1yoxaline is given below: f

Compound .A B

Rubber 55.5 55.8 Zinc oxide 12. 5 12.5 Sulphur 2. 25 2.25 Mineral nil 5.0 3. 5 Carbon hhok 24.0 24.0 Diphenyl mmnidinp .045 0.45 1-3 di para tolyl Z-Inethyl tetra hydroglyoxaline 0. 1.5 1.15

(Slabs were .cured in the press for periods of "70 2.111190 minutes air-40 pounds and test-strips .were then out out -a.nd'.tested foraging qualities both by the oxygen bomb methodand by the ifhot oven-method.

Oxygen'bombtest 48 hrs. ai -50 0. 550055 Compound A B .Rubber- 55. 8 55: s Zincn idp 12.55 12.5 Sulphur :2. 25 2. 25 Mineral nil 5.0 5 3. 5 Carbon black "24l0'; 24:0 Diphenyl guam'di 0. 45 0. 45 1-3 diphenyl 2-propen a hydroglyoxalinm 0. 1. 5

"Slabs were cured in the-press for'periods of 70 and 90 minutes zit-4.0 v pounds and. test strips were theneut out and: tested. for. agingqqualities both by the foxygen bomb; methoid. andthe .fhot

-oven -method. H

..pressure JOure 70.:540# .Cure 90x40# Com- I l' pound Tensile Elongation Tensile Elongation Q Orig. Final Orig. Final Orig. Final Orig. Final Per- Y Per- Per- Percent cent cent cent A 3910 1280 700 520 3800 1070 700 460 B 3730 2 870 730 "670 3820 2800 710 630 J Hot oven. age testtemperature 150 F.

Cure 70x40# Cure 90x 40# Days in Stock A Stock B .-Stock A Stock B oven Tens; Elong. Tens} Elong. Tens. Elong. Tens. Elong.

Pen. Per Per- Percent cent .cent cent 7145 3910 700 3730 730 3800 700 3820 710 3960 700 3935 720 3570 640 3775 670 3160 570 l 3860 680 2760 .520 3570 660 2025 460 3480 650 2205 440 p 3260 610 2050 500 2800 620 1515 350 2640 560 As an example of the use of a thio tetra hydroglyoxaline, the following rubber mixtures were Slabs were cured in a press for periods of 70 minutes and 90 minutes at 40 pounds steam pressure and strips were then cut out and tested for aging qualities.

Oxygen bomb test--48 hrs. a: C. a: 300# Oxygen Cure x 40# Cure x 40# Compound Tensile Elongation Tensile Elongation Orig. Final Orig Final Orig. Final Orig. Final Per- Per- Per- Percent cent cent ccnt 'A 3325 1385 730 570 3455 1370 740 540 B 3470 2825 700 560 3400 2790 700 650 "Hot oven test-tempe'rature 150 C.

Cute 70 x 40# Cure 90 x 40# Days in Stock A Stock B Stock A Stock B oven Tens. Elong. Tens. Elong. Tens. Elong. Tens. Elong.

Per- Per- Per- Percent cent cent cent 3325 730 3470 700 3455 740 3460 700 3390 710 3730 700 3245 670 3785 G90 2380 560 3645 670 2310 510 3420 620 1650 490 3000 630 1485 420 3030 590 1145 400 2740 580 1020 350 2640 540 800 270 2490 550 925 220 2290 490 It is also within the scope of my invention to use derivatives of tetra hydroglyoxaline in which one or more of the hydrogen atoms attached to the carbon atoms in the 4-5 position is replaced by an organic group.

As an example, I note 1-3 diphenyl 2-propyl 4-methyl tetra hydroglyoxaline, the chemical formula for which is: r

Similar substances are:

xylyl 2-furyl 4-methyl tetra hydroglyoxaline,

oxaline d1 alpha naphthy'l 2-plienyl 4-1nethy1 tetra hydroglybeta naphthyl 2-propenyl 4-niethyl tet1'a hydroglyoxaline diphenyl 4-5-dimethyl tetra hydroglyoxaline.

phenyl 2-methyl 4-ethyl tetra hydroglyoxaline,

ortho tolyl 2-vinyl 4-ethy1 tetra hydroglyoxaline,

- di xylyl 2-propyl 4-etl1yl tetra hydroglyoxaline, di alpha naphthyl 2-pl1enyl 4-ethyl tetra hydroglyoxaline, di phenyl 2-thio it-methyl tetra hydroglyoxaline, v

- (1i ortho tolyl 2-thio 4-methy1 tetra hydroglyoxaline,

- di beta naphthyl 2-pheny1 4-methyl tetra hydroglyoxaline,

- diphenyl 4-4-dimethyl tetra hydroglyoxaline,

d ortho tolyl 4-4-dimetl1yl tetra hydroglyoxaline, (11 para tolyl 4-4-dimethy1 tetra hydroglyoxaline,

(1i xylyl 44-dimethyl tetra hydroglyoxaline d i alpha naphthyl 4-4-dimethyl tetra hydroglyoxaline, dr beta naphthyl 4-4-di1nethy1 tetra hydroglyoxaline,

diphenyl 2propyl 4-pseud0 bntyl tetra hydroglyoxaline, diphenyl 24-5 trimeth l tetra hydroglyoxaline, diphenyl 2-propenyl4 -dirnethyl tetra hydroglyoxaline, diphenyl 2-propyl 4-5-dimethyl tetra hydroglyoxaline, (liphenyl 2-fury1 4-5-dimethy1 tetra hydroglyoxaline, -3 tripheny1 45dimethyl tetra hydroglyoxaline,

d phenyl 2 v1nyl 4-5-dimethyl tetra hydroglyoxaline,

d1 ortho tolyl 2-furyl 4-5-diinethyl tetra hydroglyoxaline, -3 (li para tolyl 2-pheny1 4-5-dimethyl tetra hydroglyoxadi xylyl 2-vinyl 4-5-dimethyl tetra hydroglyoxaline, d1 alpha naphthyl 2-propyl 4-5dimethyl tetra hydroglyoxaline, di beta naphthy1 2-4-5-t1-irnethvl' tetra hydroglyoxaline, d phenyl 2-4;4-tr1meth y1 tetra ydroglyoxaline, dlphenyl 2-vinyl 44-d1methyl tetra hydroglyoxaline, -3 tr1phenyl 4-4-dimethyl tetra hydroglyoxaline,

d1 ertllo tolyl 2-propyl 4-4-(limethyl tetra hydroglyoxane, diphenyl 4-4-5-trimethyl tetra hydroglyoxaline, diphen yl 2-thio 4 5-dimethyl tetra hydroglyoxaline.

To illustrate the use of 1-3 di beta naphthyl 2-phenyl 4-methyl tetra hydroglyoxaline the fol- T wcowwww lowing example is given:

Oompound v A B Rubber 56.8 56.8 Zinc oxide. 11.5 11.5 S11lpllur 2. 25 2. 25 Mineral oiL. 5. 0 3. 5 Carbon blauk. 24.0 24. 0 Diphenyl guanidine 0. 45 0. 45 1-3 di beta naphthyl 2-phenyl 4-methyl tetra hydroglyoxaline 0. 1.5

Slabs were cured in a press for periods of 70 and 90 minutes at 40 pounds steam pressure and. strips were then cut out and tested for aging qualities. The results are as follows:

Oxygen bomb test-48 hrs. :10 60- C. x 300# oxygen Cure 70 x 40# Cute 00 x 40# 53:8 Tensile Elongation Tensile Elongation Orig. Final Orig. Final Orig. Final Orig. Final Per- Per- Pcr- Percent cent cent cent A 4125 985 690 430 3795 885 650 400 B 4040 2955 680 610 3785 2820 620 570 .Hotoven testtemperatnre 150 C.

Cute 70 X401? Cute 90 X 40?; Days in Stock A Stock'B Stock A Stock 13 oven Tens. Elong. Tens Flnmz Tens. Elong. Tens. Elong.

Per- Per- Per- Percent cent cent cent 4125 690 4040 680 3795 650 3785 620 3780 000 4125 640 3660 630 3580 580 2360 520 3360 570 2230 500 3060 g 530 1705 490 3080 550 1510 420 2890 510 While the materials cited above are the free I bases, it is also possible to use salts of these materials without materially affecting the anti-oxidant value. vIn other words, the efiect of prodroglyoxaline constitution, still holds true when this material is combined to form a salt.

The tetra hydroglyoxaline derivatives referred to in this specification are prepared, in general, by the action of aldehydes on thecorresponding 1-2 diamino ethane derivativeand are considered to have the chemical constitution as given. However, I do not wish to be bound by any of the theories or formula given, but desire to protect the class of materials formed in this manner.

The thio tetra hydroglyoxaline derivatives are prepared, in general, by the action of thio 'carbonylchloride on the corresponding 1-2 diamino ethane derivative, and are considered to have the chemical constitution as given. However, I do not wish to be bound by this constitution but desire to claim that class of materials formed by the reaction of thio carbonyl chloride and 1-2 diamino ethane derivatives. Y

In general, they most beneficial effect is obtainedby using at least 1%1.5% of the material in the rubber compound, and the aging quality of the goods is, up to a certain point at least, a.

function of; the quantity of the material em ployed. v I

It has also been found possible to add the material after the rubber stock has been vulcanized and still obtain appreciable improvement in the aging qualities of the stock. -This may be done by painting or dipping the rubber stock with a solution of the desired material and, after allowing penetration totake place, to dry ofi the surplus solvent.

By the term derivative, asused in this specification and claims, it is not intended to include salts formed from strong acids whioh'in themselves are highly deleterious to the aging of rubber.

As indicated in the foregoing examples, the C atom in the 2 position of substituted 2-3 di hydroglyoxaline (or of substituted 2-3-4-5'tetra hydroglyoxaline) may have attached thereto-any of the following: H,:S,'CH3, CHaCI-Ia, CHsCHzCI-Iz, (CI-92011, CH3CH2CH2CH2, (CH3)2CI-I.CH2, CH3CH2CH2CH2CH2, (CH3) 2CH.CI-I2CH2, CsHs, C6H4CI-I3, C6H3(CH3) 2, CeI-IsCHz, CHgC H=CH, CI-12:05:, CH3CI-IzCH2CI-I =C(C2H5 .C4H30, CHsCI-IzCHzCI-IzCI-IzCI-Iz, orfin general any aliphatic, aromatic, or mixed aliphatic-aromatic groups, whether saturated or unsaturated. These radicals I consider members of the class'which may be designated, and in some of the appended claims are identified, by the term 2 modifying group. v

Independently of the special member which maybe used as a 2 modifying group, one or more of the hydrogen atoms which are attached to the nitrogen atoms in the 1-3 positions may be replaced by any of the following: CH3, CHsCHz, CI-IsCHzCI-Iz, (CH3) 2CH, CHsCHzCHzCHz, (CH3)2CI I.CI-I2, CH3CH2CH2CH2CH2, (CH3)2CH. CH2CH2, Cal-I5, C6H4CH3, C6H3(CH3)2, CsHsCHz, CH2CH=CH, CH2=CI-I, CHsCHzCHzCH C(CzHs), C4H3O, CH3CH2CH2CH2CH2CH2, or in general any aliphatic, aromatic, or mixed aliphatic-aromatic group, whether saturated or-unsaturated. These radicals I consider members of a class which may be designated, and in some of the appended claims are identified, by the term 1-3 replacement group. I r

One or both of the C atoms may alsoin. the 4-5 positions have attached thereto one or more of the following: H, CH3, CHsCHz, CHsCHzCHz, (CH3)2CH, CHsCHzCHzCHz, (CH3)2CH.CH2,

CsH4CH3, C6H3 (CH3)2 C6H5CH2, CH2CH= CI-I, CH2:-CH, -CHaCHzCHzCH=C(C2I-I5) CiHsQ, CHsCHzCHzCHzCH CHz; or in general any aliphatic, aromatic, or I mixed aliphatic-aromatic group, whether saturated or unsaturated. These I consider members of a class which may be designated, and in some of the appended claims I have identified, by the term. 4-5 modifying group.

It is-to be understood, however, that strongly negative groups suchas CeI-IsCO, CI-IaCO, or groups containing halogens, or nitro groups, may not be used in any position. of the compound.

What I claim is: n 1. A rubber. composition having incorporated therein a compound having a nucleus of the following formula: I I

in which to the 1-3-4-5 positions may be attached'any member of the, group consisting of hydrogen hydrocarbon residues, and furyl residues,-to the 2 position any member of the group consisting of-hydrogen, sulfur, hydrocarbon residues and furyl residues, said 1 compound'containing no strongly negative groups.

2. The composition described in claim 1, in which to the 1-3 position are attached aryl hydrocarbon residues.

3. The composition described in claim 1, in which to the 2 position is attached an alkyl residue. r

4. The composition described in claim 1, in which to the 1-3 positions are attached aryl hydrocarbon residues, and to the 2 position, an alkyl residue. I

5. A rubber composition having incorporated therewith "a tetrahydroglyoxaline containing no strongly negative groups and having as substituents two aryl hydrocarbon radicals.

6. A rubber composition including atetrahydroglyoxaline containing no strongly negative groups and'having as substituents in the 1-3 positions, aromatic hydrocarbon residues, in one of the 2-4-5 positions, an aliphatic hydrocarbon residue.

7. A rubber composition including therein a tetrahydroglyoxaline containing no strongly negative groups and having as substituents in'the 1-3 positions, aromatic hydrocarbon residues, in at least one of the'2-4-5 positions, an' aliphatic hydrocarbon residue, and in another of the said positions, an'aryl hydrocarbon residue.

8. Arubber composition including a tetrahydroglyoxaline having no strongly negative groups, wherein aryl hydrocarbon residues are substituted in the 1-3 positions and in at least one'ofthe 2-4-5 positions.

9. A rubber composition including a'tetrahydroglyoxaline having no strongly negative groups wherein'aromatic hydrocarbon residues are substituted in'the 1-3 positions, and an aliphatic hydrocarbon residue in the 2 position. i

10. A rubber composition including a tetrahydroglyoxaline having no strongly negative groups, wherein aryl hydrocarbon residues are substituted in the 1 -3 positions and an aliphatic hydrocarbon residue in at least one of the-4-5 positions.

11. The composition described in claim. 1, in which'one of the carbon atoms in the 4-5 positions has an additional hydrogen atom attached hereto.

'12. The composition described in claim 1, wherein each of the carbon atoms in the 4-5 positions has two hydrogen atoms attached thereto.

13. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein the carbon atom in the 2 position has attached thereto a radical which is a member of the 2 modifying group, substantially as described.

14. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein the carbon atom in the 2 position has attached thereto an aliphatic hydrocarbon radical.

15. A' rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein the carbon atom in the 2 position has attached thereto a propyl radical.

16. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein one of the H atoms attached to the N atoms in the 1-3 positions is replaced by a radical which is a member of the 1-3 replacement group.

17. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein at least one of the H atoms attached to the N atoms in the 1-3 positions is replaced by an aliphatic hydrocarbon radical.

18. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein one of the H atoms attached to the N atoms in the 1-3 positions is replaced by an aromatic hydrocarbon radical.

19. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein one of the H atoms attached to the N atoms in the 1-3 positions is replaced by a phenyl radical.

20. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein both hydrogen atoms attached to the N atoms in the 1-3 positions are replaced by a radical which is a member of the 1-3 replacement group.

21. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein both hydrogen atoms attached to the N atoms in the 1-3 positions are replaced by an aromatic hydrocarbon radical.

'22. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein both hydrogen atoms attached to the N atoms in the 1-3 positions are replaced by a phenyl radical.

23. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein one of the carbon atoms in the 4-5 positions has a radical attached thereto which is a member of the 4-5 modifying group.

24. A rubber composition including a tetra hydroglyoxaline having no strongly negative groups wherein one of the carbon atoms in'the 4-5 positions has two radicals attached thereto which are members of the 4-5 modifying group.

'27. A rubber compositionincluding 1-3 diphenyl 2-propyl tetra hydroglyoxaline.

28. A rubber composition having incorporated therewith a substituted hydroglyoxaline containing no strongly negative groups.

29. A rubber composition having incorporated therewith dihydroglyoxaline containing no strongly negative groups.

30. A rubber composition having incorporated therewith a substituted tetrahydroglyoxaline containing no strongly negative groups. I

31. The method of improving the aging qualities of rubber products which comprises incorporating in the rubber mix a small amount of a condensation product of an aldehyde with an alkylene diaryl diamine and subjecting the resulting mixture to vulcanization.

32. The method of improving the aging qualities of rubber products which comprises incorporating in the rubber mix a small amount of a condensation product of an aldehyde with ethylene diphenyl diamine.

33. A new rubber composition containing a condensation product of an aldehyde with an alkylene diaryl diamine.

34. A vulcanized rubber composition combined before vulcanization with a small amount of a condensation product of an aldehyde'with ethylene diphenyl diamine.

35. The method of retarding deterioration of rubber which comprises treating rubber with a condensation product of a ditolyl alkylene diamine with an aldehyde.

36. An age-resisting rubber composition comprising rubber treated with a condensation product of a ditolyl alkylene diamine with an aldehyde.

37. A rubber composition having incorporated therein a hydroglyoxaline containing no strongly negative groups but having its 2-position substituted with a member of the 2-modifying group.

38. The composition of claim 37 in which the said hydroglyoxaline has at least one of the hydrogen atoms in the 1-3-positions replaced'by a'member of the 1-3 replacement group.

39. The composition of claim 3'? in which at least one of the 4-5-positions of the hydroglyoxaline is substituted with a member of the 4-5 modifying group.

40. The composition of claim 1 wherein at least one of the land S-positions is substituted with a member of the 1-3 replacement group, the 2- position is substituted with a member of the 2- modifying group and at least one of the 4-5 positions is substituted with a member of the 4-5 modifying group. 7 r

41. A rubber composition having incorporated therein a small proportion of 2-4-5 trifuryl di hydroglyoxaline.

42. A rubber composition having incorporated therein a small proportion of 1-3 di alpha naphthyl tetra hydroglyoxaline.

43. A rubber composition having incorporated therein a small proportion of a hydroglyoxaline selected from a class consistingof 2-4-5 trifuryl di hydroglyoxaline, 1-3 di alpha naphthyl tetra hydroglyoxaline, 1-3 diphenyl 2-propyl tetra hydroglyoxaline, 1-3 di para tolyl 2-phenyl tetra hydroglyoxaline, l -3 diphenyl 2-propenyl tetra hydroglyoxaline, 1-3 di para tolyl 2-methyl tetra hydroglyoxaline, 1 phenyl 3-Xylyl 2-thio tetra hydroglyoxaline, and 1-3 di beta naphthyl 2- phenyl 4-methyl tetra hydroglyoxaline.

HAROLD A. MORTON. 

